1. Field of Technology
The present invention relates to an improvement in a gas-discharge display device with matrix display panel.
2. Prior Arts
A gas discharge display device with a matrix display panel has been previously disclosed by Skellet, with a construction such as shown in FIG. 1. In FIG. 1, a parallel array of cathodes K.sub.R, K.sub.1,--, K.sub.n and a parallel array of anodes A.sub.1,--, A.sub.m are disposed in a space defined between two parallel glass plates. The parallel array of cathodes and anodes are spaced from each other and are disposed at right angles with respect to each other. A discharging gas mixture mainly consisting of neon is confined in the space between the glass plates, and D.C. voltages are applied between selected one(s) of the cathodes and selected one(s) of the anodes.
Such a type of device is very simple in construction, and therefore has advantages from the view point of manufacture. However, when many discharge dots, which are defined by the crossing portions of anodes and cathodes, are intended to be simultaneously lit, then there is a possibility of cross-talk. That is, there is a possibility of undesirable lighting at cross points other than those intended to be lit. Because of the cross-talk, this simply structured device has not entered into wide practical use.
Thereafter, two different types of improved gas-discharge devices have been disclosed, and have come into practical use. One of them is known as an A.C. type or Illinois type device and is shown in FIG. 2. In this construction both the X-electrodes array 3 and Y-electrodes array 4 are covered with a dielectric material layer 5 and the lighting of dots or cross points is achieved by impressing A.C. voltages between them.
The other different type is known as a D.C. discharge type or Burroughs Corporation type and is shown in FIG. 3. In this construction a pair of a scanning anode A' and a displaying anode A are utilized. In the improved devices shown in FIG. 2 and FIG. 3, cross-talk can be prevented, thereby assuring a stable display. However, these devices have a more complicated structure than the device of FIG. 1, and accordingly are difficult and expensive to manufacture and require a more complicated driving circuit. Specifically, for the A.C. type device of FIG. 2, the driving circuit must contain a discharge sustaining circuit in addition to an address circuit. For the D.C. type device of FIG. 3, a scanning circuit is required in addition to the displaying circuit.